The nuclear and extended infrared emission of the

A high spatial resolution study of the
extended emission in Seyfert Galaxies
The nuclear and extended infrared emission of
the Seyfert galaxy NGC 2992 and the
interacting system Arp 245
I. García-Bernete, C. Ramos Almeida, J. A. Acosta-Pulido, et al., 2015,
MNRAS, 449, 1309
EWASS 2015, La Laguna (Spain)
The central engines AGN

Unified Model (Antonucci 1993)
The AGN type depends on orientation

Seyfert torus size ~ few pc
(Tristram et al. 2009; Burstcher et al. 2013)

The torus absorbs the intrinsic AGN
radiation and re-emits it in the IR,
peaking in the MIR
Orientation
Credit: W. Steffen (UNAM)
The central engines AGN

Unified Model (Antonucci 1993)
The AGN type depends on orientation

Seyfert torus size ~ few pc
(Tristram et al. 2009; Burstcher et al. 2013)

The torus absorbs the intrinsic AGN
radiation and re-emits it in the IR,
peaking in the MIR
Orientation
Credit: W. Steffen (UNAM)
The central engines AGN

Unified Model (Antonucci 1993)
The AGN type depends on orientation

Seyfert torus size ~ few pc
(Tristram et al. 2009; Burstcher et al. 2013)

The torus absorbs the intrinsic AGN
radiation and re-emits it in the IR,
peaking in the MIR
Orientation
Credit: W. Steffen (UNAM)
The central engines AGN

Unified Model (Antonucci 1993)
The AGN type depends on orientation

Seyfert torus size ~ few pc
(Tristram et al. 2009; Burstcher et al. 2013)

The torus absorbs the intrinsic AGN
radiation and re-emits it in the IR,
peaking in the MIR
Orientation
Black Hole
Accretion disk
Clumpy torus
MIR
Cold dust
FIR
Credit: W. Steffen (UNAM)
Mid-IR imaging: space (Spitzer/IRAC) vs.
ground (Gemini/T-ReCS) observations
Díaz-Santos (2009, PhD)
Mid-IR imaging: space (Spitzer/IRAC) vs.
ground (Gemini/T-ReCS) observations
Díaz-Santos (2009, PhD)
The infrared emission of the Seyfert 2 galaxy NGC 2992
Spitzer and Herschel
Gemini and Hubble
NGC 2992: infrared photometry
Recovering nuclear information from low angular resolution data
Nuclear IR SED modelling with
clumpy torus models
●
Different methods to try to recover the
nuclear information from arcsecond
resolution data:
Apert. Photometry & Scaled PSF subtraction.
Torus emission dominates
NGC 2992: spectral decomposition of Spitzer spectrum
Recovering nuclear information from low angular resolution data
Decomposition (AGN + SB):

Generic torus model from Ramos Almeida et al. 2011

SB templates from Rieke et al. 2009 & Brand et al. 2006
Spitzer/IRS
spectrum
AGN contribution
Model
90%
GTC/Canaricam
spectrum
30%
AGN
AGN emission dominates at ~20-30 micron !
SB
GTC/CanariCam MIR spectra of NGC 2992

Nuclear spectra (~ 60 pc)

No SF or PAH features diluted by
the AGN continuum.
Size of the region probed by
Spitzer/IRS ~ 640 pc

Extended emission spectra (~ 900 pc)

PAH features!I
Dust heated by SF
Arp 245 interacting system
Physical parameters of the circumnuclear dust emission derived from
Sptizer and Herschel data
Warm Cold
Very
cold
(a) Circumnuclear dust
(b) Galaxy disk dust
Very similar dust masses, temperatures and
SFRs for NGC 2992/2993
Conclusions
●
●
We reproduced the nuclear IR SED of NGC 2992 with clumpy torus models
and derived its torus properties.
We recovered the nuclear emission from low angular resolution data:
●
●
●
Photometry: nuclear fluxes in the range ~20-30, where the torus emission
dominates.
●
Spectroscopy: flux and spectral shape.
●
The torus emission dominates at ~20-30.
The GTC/CanariCam nuclear spectrum reveals NO/DILUTED PAH
emission in the central ~ 60 pc of NGC 2992.
Dust emission properties of Arp 245 system using dust models
●
We derived very similar dust masses, temperatures and SFRs for both spiral
galaxies.
I. García-Bernete, C. Ramos Almeida, J. A. Acosta-Pulido, et al., 2015, MNRAS, 449, 1309
Conclusions
●
●
We reproduced the nuclear IR SED of NGC 2992 with clumpy torus models
and derived its torus properties.
We recovered the nuclear emission from low angular resolution data:
●
●
●
Photometry: nuclear fluxes in the range ~20-30, where the torus emission
dominates.
●
Spectroscopy: flux and spectral shape.
●
The torus emission dominates at ~20-30.
The GTC/CanariCam nuclear spectrum reveals NO/DILUTED PAH
emission in the central ~ 60 pc of NGC 2992.
Dust emission properties of Arp 245 system using dust models
●
We derived very similar dust masses, temperatures and SFRs for both spiral
galaxies.
I. García-Bernete, C. Ramos Almeida, J. A. Acosta-Pulido, et al., 2015, MNRAS, 449, 1309
Thank you!
Email: [email protected]

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